Microsoft today said it will update its popular Desktop Optimization Pack  with additional virtualization software now that its acquisition of Kidaro has been finalized.

The Kidaro software lets users run multiple versions of Windows and applications concurrently without having to open multiple virtual machine sessions. Microsoft has rebranded the Kidaro software as Microsoft Enterprise Desktop Virtualization and will release it in the first half of 2009.

“We will continue investing here because we know manageability is fundamental to broad corporate use of desktop virtualization,” wrote Shanen Boettcher, GM of Windows product management, on the Vista Team Blog.

The Microsoft Desktop Optimization Pack, or MDOP, is designed to help IT administrators manage collections of Windows desktops. It includes Application Virtualization to stream applications from a centrally managed service; Asset Inventory Service, an inventory scanning tool; System Center Desktop Error Monitoring; Advanced Group Policy Management (APGM) for change management via group policy objects; and the Diagnostics and Recovery Toolset, which helps in recovering a crashed PC.

MDOP is comprised of software from Microsoft’s purchases of Softricity, AssetMetrix, Winternals Software and DesktopStandard.

MDOP, which is available only to users with Software Assurance maintenance contracts, has become the fastest-selling volume licensing product in Microsoft’s history, with more than 6.5 million licenses.

Microsoft said in April at its annual Management Summit that it will release this fall the next version of MDOP, part of an update cycle that will happen every six months. The last update was in April.

Microsoft said the fall release would extend MDOP to 10 languages beyond its current English-only release. The languages are Chinese Simplified, Chinese Traditional, German, French, Italian, Japanese, Korean, Brazilian Portuguese, Russian and Spanish.

Other MDOP updates include the fall release of Asset Inventory Service 1.5, which will add license reconciliation along with scalability improvements, and Advanced Group Policy Management 3.0, which adds support for Windows Vista SP1 and Windows Server 2008, new security features, and enhanced reporting.